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McDonald R, Sadler C, Kumar TR. Gain-of-Function Genetic Models to Study FSH Action. Front Endocrinol (Lausanne) 2019; 10:28. [PMID: 30792692 PMCID: PMC6374295 DOI: 10.3389/fendo.2019.00028] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 01/15/2019] [Indexed: 12/15/2022] Open
Abstract
Follicle-stimulating hormone (FSH) is a pituitary-derived gonadotropin that plays key roles in male and female reproduction. The physiology and biochemistry of FSH have been extensively studied for many years. Beginning in the early 1990s, coincident with advances in the then emerging transgenic animal technology, and continuing till today, several gain-of-function (GOF) models have been developed to understand FSH homeostasis in a physiological context. Our group and others have generated a number of FSH ligand and receptor GOF mouse models. An FSH GOF model when combined with Fshb null mice provides a powerful genetic rescue platform. In this chapter, we discuss different GOF models for FSH synthesis, secretion and action and describe additional novel genetic models that could be developed in the future to further refine the existing models.
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Affiliation(s)
- Rosemary McDonald
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, IL, United States
- Integrated Physiology Graduate Program, University of Colorado Anschutz Medical CampusAurora, IL, United States
| | - Carolyn Sadler
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, IL, United States
| | - T. Rajendra Kumar
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, IL, United States
- Integrated Physiology Graduate Program, University of Colorado Anschutz Medical CampusAurora, IL, United States
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical CampusAurora, IL, United States
- *Correspondence: T. Rajendra Kumar
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Dan L, Liu S, Shang S, Zhang H, Zhang R, Li N. Expression of recombinant human lysozyme in bacterial artificial chromosome transgenic mice promotes the growth of Bifidobacterium and inhibits the growth of Salmonella in the intestine. J Biotechnol 2018; 272-273:33-39. [PMID: 29549001 DOI: 10.1016/j.jbiotec.2018.03.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 02/20/2018] [Accepted: 03/06/2018] [Indexed: 10/17/2022]
Abstract
Targeted gene modification is a novel intervention strategy to increase disease resistance more quickly than traditional animal breeding. Human lysozyme, a natural, non-specific immune factor, participates in innate immunity, exerts a wide range of antimicrobial activities against pathogens, and has immuneregulatory effects. Therefore, it is a candidate gene for improved disease resistance in animals. In this study, we successfully generated a transgenic mouse model by microinjecting a modified bacterial artificial chromosome containing a recombinant human lysozyme (rhLZ) gene into the pronuclei of fertilized mouse embryos. rhLZ was expressed in serum, liver, spleen, lung, kidney, stomach, small intestine, and large intestine but not in milk. rhLZ protein concentrations in the serum of transgenic mice ranged from 2.09 to 2.60 mg/l. To examine the effect of rhLZ on intestinal microbiota, total aerobes, total anaerobes, Clostridium, Enterococcus, Streptococcus, Salmonella, Escherichia coli, Staphylococcus, Bifidobacterium, and Lactobacillus were measured in the intestines of transgenic and wild type mice. Results showed that Bifidobacteria were significantly increased (p < 0.001), whereas Salmonella were significantly decreased (p < 0.001) in transgenic mice compared to wild type mice. Our study suggests that rhLZ expression is a potential strategy to increase animal disease resistance.
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Affiliation(s)
- Lu Dan
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, China; Shanghai Institute of Medical Genetics, Shanghai Children's Hospital, Shanghai Jiao Tong University, Shanghai 200040, China.
| | - Shen Liu
- School of Life Science and Engineering, Foshan University, Foshan 528000, China
| | - Shengzhe Shang
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, China
| | - Huihua Zhang
- School of Life Science and Engineering, Foshan University, Foshan 528000, China
| | - Ran Zhang
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, China
| | - Ning Li
- State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, China.
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Li W, Quan Y, Zhang M, Wang K, Zhu M, Chen Y, Li Q, Wu K. Effects of pituitary-specific overexpression of FSHα/β on reproductive traits in transgenic boars. J Anim Sci Biotechnol 2017; 8:84. [PMID: 29090093 PMCID: PMC5655851 DOI: 10.1186/s40104-017-0208-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 08/29/2017] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Follicle-stimulating hormone (FSH) is a gonadotropin synthesized and secreted by the pituitary gland. FSH stimulates follicle development and maturation in females. It also plays an important role in spermatogenesis in males, including humans and mice. However, the effects of FSH on male pigs are largely unknown. In this study, we generated transgenic pigs to investigate the effects of FSHα/β overexpression on reproductive traits in boars. RESULTS After five transgenic F0 founders were crossed with wide-type pigs, 193 F1 animals were obtained. Of these, 96 were confirmed as transgenic. FSHα and FSHβ mRNAs were detected only in pituitary tissue. Transgenic boars exhibited significantly higher levels of FSHα and FSHβ mRNA, serum FSH, and serum testosterone, compared to full-sib non-transgenic boars. Significant increases in testis weight, vas deferens diameter, seminiferous tubule diameter, and the number of Leydig cells were observed, suggesting that the exogenous FSHα/β affects reproductive traits. Finally, transgenic and non-transgenic boars had similar growth performance and biochemical profiles. CONCLUSIONS Pituitary-specific overexpression of FSHα/β genes is likely to impact reproductive traits positively, as indicated by enhancements in serum testosterone level, testis weight, the development of vas deferens, seminiferous tubules, and Leydig cells in transgenic boars. A high level of serum FSH induces secretion of serum testosterone, possibly by boosting the number of Leydig cells, which presumably increases the libido and the frequency of sexual activity in transgenic boars. Our study provides a preliminary foundation for the genetic improvement of reproductive traits in male pigs.
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Affiliation(s)
- Wenting Li
- College of Animal Science and Technology, China Agricultural University, Beijing, 100193 China
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002 China
| | - Yujun Quan
- College of Animal Science and Technology, China Agricultural University, Beijing, 100193 China
- Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101 China
| | - Mengmeng Zhang
- College of Animal Science and Technology, China Agricultural University, Beijing, 100193 China
| | - Kejun Wang
- College of Animal Science and Technology, China Agricultural University, Beijing, 100193 China
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002 China
| | - Muzhen Zhu
- College of Animal Science and Technology, China Agricultural University, Beijing, 100193 China
| | - Ye Chen
- The Department of Animal Husbandry, Rongchang Campus, Southwest University, Rongchang, Chongqing, 402460 China
| | - Qiuyan Li
- State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing, 100193 China
| | - Keliang Wu
- College of Animal Science and Technology, China Agricultural University, Beijing, 100193 China
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Jiang K, Xu P, Li W, Yang Q, Li L, Qiao C, Gong H, Zheng H, Zhou Z, Fu H, Li Q, Xing Y, Ren J. The increased expression of follicle-stimulating hormone leads to a decrease of fecundity in transgenic Large White female pigs. Transgenic Res 2017. [PMID: 28631185 DOI: 10.1007/s11248-017-0026-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Follicle-stimulating hormone (FSH) is a pituitary gonadotropin regulating reproduction in mammals. Overexpression of the exogenous FSHα/β genes from Chinese Erhualian pigs improved female fecundity of transgenic (TG) mice and male spermatogenesis ability of Large White TG boars. Here, we investigated the impact of the exogenous FSHα/β genes on female reproductive performance of Large White TG pigs. First, we identified the integration site of the exogenous FSHα/β genes at 140,646,456 bp on chromosome 9 in these TG pigs using whole-genome sequencing. Then, we showed that TG gilts had higher levels of serum FSH and FSHβ protein in pituitary while had a potentially lower number of born piglets than their wild-type half sibs. TG gilts grew healthily and normally without significant difference in growth and health parameters as compared to WT gilts. The expression levels of FSHR, LHR, ESR1 and ESR2 were significantly lower in TG gilts than in WT gilts at the age of 300 days. Taken together, we proposed that the overexpressed FSHα/β transgenes could cause deteriorate fecundity via disturbing the normal expression of the endogenous reproduction-related genes in female pigs. Our findings provide insight into the effect of overexpression of FSHα/β on female reproduction performance in pigs.
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Affiliation(s)
- Kai Jiang
- State Key Laboratory of Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Pan Xu
- State Key Laboratory of Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China.,Jiangsu Agri-animal Husbandry Vocational College, Taizhou, 225300, People's Republic of China
| | - Wanbo Li
- State Key Laboratory of Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Qiang Yang
- State Key Laboratory of Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Longyun Li
- State Key Laboratory of Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Chuanmin Qiao
- State Key Laboratory of Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Huanfa Gong
- State Key Laboratory of Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Hao Zheng
- State Key Laboratory of Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Zhimin Zhou
- State Key Laboratory of Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Hao Fu
- State Key Laboratory of Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Qiuyan Li
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, People's Republic of China
| | - Yuyun Xing
- State Key Laboratory of Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China.
| | - Jun Ren
- State Key Laboratory of Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
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BAC mediated transgenic Large White boars with FSHα/β genes from Chinese Erhualian pigs. Transgenic Res 2016; 25:693-709. [PMID: 27229510 DOI: 10.1007/s11248-016-9963-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 05/19/2016] [Indexed: 10/21/2022]
Abstract
Follicle-stimulating hormone (FSH) is a critical hormone regulating reproduction in mammals. Transgenic mice show that overexpression of FSH can improve female fecundity. Using a bacterial artificial chromosome (BAC) system and somatic cell nuclear transfer, we herein generated 67 Large White transgenic (TG) boars harboring FSHα/β genes from Chinese Erhualian pigs, the most prolific breed in the world. We selected two F0 TG boars for further breeding and conducted molecular characterization and biosafety assessment for F1 boars. We showed that 8-9 copies of exogenous FSHα and 5-6 copies of exogenous FSHβ were integrated into the genome of transgenic pigs. The inheritance of exogenous genes conforms to the Mendel's law of segregation. TG boars had higher levels of serum FSH, FSHα mRNA in multiple tissues, FSHβ protein in pituitary and more germ cells per seminiferous tubule compared with their wild-type half sibs without any reproductive defects. Analysis of growth curve, hematological and biochemical parameters and histopathology illustrated that TG boars grew healthily and normally. By applying 16S rRNA gene sequencing, we demonstrated that exogenous genes had no impact on the bacterial community structures of pig guts. Moreover, foreign gene drift did not occur as verified by horizontal gene transfer. Our findings indicate that overexpression of FSH could improve spermatogenesis ability of boars. This work provides insight into the effect of FSHα/β genes on male reproductive performance on pigs by a BAC-mediated transgenic approach.
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Bernstein LR, Mackenzie ACL, Lee SJ, Chaffin CL, Merchenthaler I. Activin Decoy Receptor ActRIIB:Fc Lowers FSH and Therapeutically Restores Oocyte Yield, Prevents Oocyte Chromosome Misalignments and Spindle Aberrations, and Increases Fertility in Midlife Female SAMP8 Mice. Endocrinology 2016; 157:1234-47. [PMID: 26713784 PMCID: PMC4769367 DOI: 10.1210/en.2015-1702] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Women of advanced maternal age (AMA) (age ≥ 35) have increased rates of infertility, miscarriages, and trisomic pregnancies. Collectively these conditions are called "egg infertility." A root cause of egg infertility is increased rates of oocyte aneuploidy with age. AMA women often have elevated endogenous FSH. Female senescence-accelerated mouse-prone-8 (SAMP8) has increased rates of oocyte spindle aberrations, diminished fertility, and rising endogenous FSH with age. We hypothesize that elevated FSH during the oocyte's FSH-responsive growth period is a cause of abnormalities in the meiotic spindle. We report that eggs from SAMP8 mice treated with equine chorionic gonadotropin (eCG) for the period of oocyte growth have increased chromosome and spindle misalignments. Activin is a molecule that raises FSH, and ActRIIB:Fc is an activin decoy receptor that binds and sequesters activin. We report that ActRIIB:Fc treatment of midlife SAMP8 mice for the duration of oocyte growth lowers FSH, prevents egg chromosome and spindle misalignments, and increases litter sizes. AMA patients can also have poor responsiveness to FSH stimulation. We report that although eCG lowers yields of viable oocytes, ActRIIB:Fc increases yields of viable oocytes. ActRIIB:Fc and eCG cotreatment markedly reduces yields of viable oocytes. These data are consistent with the hypothesis that elevated FSH contributes to egg aneuploidy, declining fertility, and poor ovarian response and that ActRIIB:Fc can prevent egg aneuploidy, increase fertility, and improve ovarian response. Future studies will continue to examine whether ActRIIB:Fc works via FSH and/or other pathways and whether ActRIIB:Fc can prevent aneuploidy, increase fertility, and improve stimulation responsiveness in AMA women.
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Affiliation(s)
- Lori R Bernstein
- Pregmama, LLC (L.R.B.), Gaithersburg, Maryland 20886; Departments of Epidemiology and Public Health (L.R.B., A.C.L.M., I.M.), Obstetrics, Gynecology, and Reproductive Sciences (C.L.C.), and Anatomy and Neurobiology (I.M.), University of Maryland School of Medicine, Baltimore, Maryland 21201; Departments of Molecular Biology and Genetics (S.-J.L.) and Gynecology and Obstetrics, Johns Hopkins University School of Medicine (L.R.B.), Baltimore, Maryland 21205; and Department of Veterinary Integrative Biosciences (L.R.B.), Texas A&M College of Veterinary Medicine, College Station, Texas 77843
| | - Amelia C L Mackenzie
- Pregmama, LLC (L.R.B.), Gaithersburg, Maryland 20886; Departments of Epidemiology and Public Health (L.R.B., A.C.L.M., I.M.), Obstetrics, Gynecology, and Reproductive Sciences (C.L.C.), and Anatomy and Neurobiology (I.M.), University of Maryland School of Medicine, Baltimore, Maryland 21201; Departments of Molecular Biology and Genetics (S.-J.L.) and Gynecology and Obstetrics, Johns Hopkins University School of Medicine (L.R.B.), Baltimore, Maryland 21205; and Department of Veterinary Integrative Biosciences (L.R.B.), Texas A&M College of Veterinary Medicine, College Station, Texas 77843
| | - Se-Jin Lee
- Pregmama, LLC (L.R.B.), Gaithersburg, Maryland 20886; Departments of Epidemiology and Public Health (L.R.B., A.C.L.M., I.M.), Obstetrics, Gynecology, and Reproductive Sciences (C.L.C.), and Anatomy and Neurobiology (I.M.), University of Maryland School of Medicine, Baltimore, Maryland 21201; Departments of Molecular Biology and Genetics (S.-J.L.) and Gynecology and Obstetrics, Johns Hopkins University School of Medicine (L.R.B.), Baltimore, Maryland 21205; and Department of Veterinary Integrative Biosciences (L.R.B.), Texas A&M College of Veterinary Medicine, College Station, Texas 77843
| | - Charles L Chaffin
- Pregmama, LLC (L.R.B.), Gaithersburg, Maryland 20886; Departments of Epidemiology and Public Health (L.R.B., A.C.L.M., I.M.), Obstetrics, Gynecology, and Reproductive Sciences (C.L.C.), and Anatomy and Neurobiology (I.M.), University of Maryland School of Medicine, Baltimore, Maryland 21201; Departments of Molecular Biology and Genetics (S.-J.L.) and Gynecology and Obstetrics, Johns Hopkins University School of Medicine (L.R.B.), Baltimore, Maryland 21205; and Department of Veterinary Integrative Biosciences (L.R.B.), Texas A&M College of Veterinary Medicine, College Station, Texas 77843
| | - István Merchenthaler
- Pregmama, LLC (L.R.B.), Gaithersburg, Maryland 20886; Departments of Epidemiology and Public Health (L.R.B., A.C.L.M., I.M.), Obstetrics, Gynecology, and Reproductive Sciences (C.L.C.), and Anatomy and Neurobiology (I.M.), University of Maryland School of Medicine, Baltimore, Maryland 21201; Departments of Molecular Biology and Genetics (S.-J.L.) and Gynecology and Obstetrics, Johns Hopkins University School of Medicine (L.R.B.), Baltimore, Maryland 21205; and Department of Veterinary Integrative Biosciences (L.R.B.), Texas A&M College of Veterinary Medicine, College Station, Texas 77843
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Lu D, Liu S, Shang S, Wu F, Wen X, Li Z, Li Y, Hu X, Zhao Y, Li Q, Li N. Production of transgenic-cloned pigs expressing large quantities of recombinant human lysozyme in milk. PLoS One 2015; 10:e0123551. [PMID: 25955256 PMCID: PMC4425539 DOI: 10.1371/journal.pone.0123551] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 03/05/2015] [Indexed: 11/25/2022] Open
Abstract
Human lysozyme is a natural non-specific immune factor in human milk that plays an important role in the defense of breastfed infants against pathogen infection. Although lysozyme is abundant in human milk, there is only trace quantities in pig milk. Here, we successfully generated transgenic cloned pigs with the expression vector pBAC-hLF-hLZ-Neo and their first generation hybrids (F1). The highest concentration of recombinant human lysozyme (rhLZ) with in vitro bioactivity was 2759.6 ± 265.0 mg/L in the milk of F0 sows. Compared with wild-type milk, rhLZ milk inhibited growth of Escherichia coli K88 during the exponential growth phase. Moreover, rhLZ in milk from transgenic sows was directly absorbed by the intestine of piglets with no observable anaphylactic reaction. Our strategy may provide a powerful tool for large-scale production of this important human protein in pigs to improve resistance to pathogen infection.
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Affiliation(s)
- Dan Lu
- The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China
| | - Shen Liu
- The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China
| | - Shengzhe Shang
- The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China
| | - Fangfang Wu
- College of Animal Science and Technology, Yunnan Agricultural University, Kunming, China
| | - Xiao Wen
- Beijing Genfucare Biotechnology Company, Beijing, China
| | - Zhiyuan Li
- Beijing Genfucare Biotechnology Company, Beijing, China
| | - Yan Li
- Beijing Genfucare Biotechnology Company, Beijing, China
| | - Xiaoxiang Hu
- The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China
| | - Yaofeng Zhao
- The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China
| | - Qiuyan Li
- The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China
| | - Ning Li
- The State Key Laboratory for Agro-biotechnology, China Agricultural University, Beijing, China
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Zhang Y, Dai Z, Wu G, Zhang R, Dai Y, Li N. Expression of threonine-biosynthetic genes in mammalian cells and transgenic mice. Amino Acids 2014; 46:2177-88. [PMID: 24893662 DOI: 10.1007/s00726-014-1769-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Accepted: 05/21/2014] [Indexed: 12/16/2022]
Abstract
Threonine is a nutritionally essential amino acid (EAA) for the growth and development of humans and other nonruminant animals and must be provided in diets to sustain life. The aim of this study was to synthesize threonine in mammalian cells through transgenic techniques. To achieve this goal, we combined the genes involved in bacterial threonine biosynthesis pathways into a single open reading frame separated by self-cleaving peptides (2A) and then linked it into a transposon system (piggyBac). The plasmids pEF1a-IRES-GFP-E2F-his and pEF1a-IRES-GFP-M2F-his expressed Escherichia coli homoserine kinase and threonine synthase efficiently in mouse cells and enabled cells to synthesize threonine from homoserine. This biosynthetic pathway occurred with a low level of efficiency in transgenic mice. Three transgenic mice were identified by Southern blot from 72 newborn mice, raising the possibility that a high level of expression of these genes in mouse embryos might be lethal. The results indicated that it is feasible to synthesize threonine in animal cells using genetic engineering technology. Further work is required to improve the efficiency of this method for introducing genes into mammals. We propose that the transgenic technology provides a promising means to enhance the synthesis of nutritionally EAAs in farm animals and to eliminate or reduce supplementation of these nutrients in diets for livestock, poultry and fish.
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Affiliation(s)
- Yurui Zhang
- State Key Laboratory for Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
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